Romans 2:28

For he is not a Jew which is one outwardly
The apostle removes the plea in favour of the Jews, taken from their name and privilege, by distinguishing between a Jew and a Jew, and between circumcision and circumcision: "he is not a Jew which is one outwardly"; by mere name, nature, nation, religion, and profession:

neither is that circumcision which is outward in the flesh;
which takes away the flesh of the foreskin, but not the carnality of the heart; leaves a mark upon the flesh, but no impression on the mind. This is nothing, is not the true, solid, substantial, spiritual circumcision, which only avails in the sight of God.